Pit pump

ABSTRACT

The invention provides a pit pump having a submersible hydraulic drive motor, a pump, and a bearing block assembly. The pump has a body, a fluid inlet in the body, a fluid outlet in the body, and an impeller operatively positioned in the body, whereby fluid can be pumped between the fluid inlet and the fluid outlet. The bearing block assembly operatively connects the hydraulic drive motor to the impeller of the pump, whereby the submersible hydraulic drive motor is spaced apart from the pump. The bearing block assembly preferably includes a housing and a drive shaft operatively positioned for rotational movement within the housing, whereby rotational movement can be transferred from the hydraulic drive motor to the impeller of the pump. The bearing block assembly preferably has at least one grease nipple and at least one bleeder nipple for maintaining grease lubrication within the bearing block assembly. Furthermore, the bearing block assembly is preferably lubricated with an extreme-pressure, water-resistant, and high-temperature grease.

TECHNICAL FIELD

[0001] The present invention relates to a pump for circulating or removing heavy liquids, such as mud, sludge, or slurry from a pit or tank.

SUMMARY OF THE INVENTION

[0002] The invention provides a pit pump having a submersible hydraulic drive motor, a pump, and a bearing block assembly. The pump has a body, a fluid inlet in the body, a fluid outlet in the body, and an impeller operatively positioned in the body, whereby fluid can be pumped between the fluid inlet and the fluid outlet. The bearing block assembly operatively connects the hydraulic drive motor to the impeller of the pump, whereby the submersible hydraulic drive motor is spaced apart from the

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The accompanying drawings are incorporated into and form a part of the specification to illustrate several examples of the present inventions. These drawings together with the description serve to explain the principals of the invention. The drawings are only for the purpose of illustrating preferred and alternative examples of how the invention can be made and used and are not to be construed as limiting the invention to only the illustrated and described examples. The various advantages and features of the present invention will be apparent from a consideration of the drawings in which:

[0004]FIG. 1 is an exploded view of a pit pump according to the presently most preferred embodiment of the invention.

DETAILED DESCRIPTION OF PRESENTLY MOST-PREFERRED EMBODIMENTS OF THE INVENTION

[0005] As used herein, the word fluid includes any fluid that can be pumped, including heaving liquids such as mud, sludge, and slurry.

[0006] The present invention will be described by referring to drawings of apparatus and methods of use showing various examples of how the invention can be made and used. Referring to FIG. 1 of the drawing, a pit pump according to the invention is illustrated. According to the presently most-preferred embodiment of the invention, the pit pump generally includes a hydraulic drive motor 3, a bearing block assembly 7, and a pump 28.

[0007] The illustrated pit pump is for a 3″ or 4″ pump size, but as can be appreciated by those skilled in the art, is substantially representative of any convenient size, such as a 6″ pump size. The overall size and weight of the pit pump is still convenient for ease of putting the pump in a pit or tank or retrieving it from the pit or tank as needed.

[0008] The hydraulic drive motor 3 is preferably provided with appropriate hydraulic fittings 24, each of which is equipped with an appropriate quick coupler, such as a ½″ quick coupler (male) 23, and a ½″ quick coupler (female) 25. The quick couplers can be used to quickly attach or remove appropriate hydraulic hoses to supply the hydraulic fluid for operating the drive motor 3. The use of a hydraulic drive motor 3 is much safer than the use of an electrical motor, eliminating the risk of spark or fire associated with electrically-operated equipment.

[0009] The pump 28 has a pump body 20, which preferably includes a pump lid 12. The pump lid 12 is sealed with the pump body 20 with an appropriate seal, such as a ⅛″ neoprene rubber gasket 15. The pump lid 12 can be removably secured to the rest of the pump body 20 using, for example, a plurality of ½″×1-¼″ UNC bolts 10 with ½″ SAE washers 11. The lid 12 of the pump body allows the interior of the pump to be accessible for assembly and maintenance of the pump.

[0010] The interior of the pump body 20 has an appropriate fluid inlet port (not shown) that is spaced apart from an appropriate fluid outlet 29. The pump body 20 also provides an appropriate impeller cavity 30 for positioning an impeller 18 for rotational movement within the pump body 20. The impeller 18 is adapted for rotation within the impeller cavity 30.

[0011] Upon rotation of the impeller, it draws fluid through the inlet port and expels it through the outlet port 29. The pump body 20 and the impeller 18 can be made of any metal or plastic material that has sufficient strength and toughness for the desired application. According to the presently most-preferred embodiment, the pump body and impeller are made of a strong metal material, such as an iron based material.

[0012] According to the presently most-preferred embodiment of the invention, the inlet port is positioned on a lower facing surface of the pump body 20, and the pump body 20 preferably has a plurality of downwardly extending tabs 31 to help prevent the fluid inlet port from becoming blocked by the bottom of the pit or tank on which the pit pump rests. So long as the pump 28 can be primed, the inlet port can be, but does not need to be at the very bottom of the pit or tank.

[0013] According to the presently most-preferred embodiment of the invention, the outlet port 29 has an appropriate adapter portion, which can be used for connecting pipe or flexible conduit, for transferring fluid away from the pump and out of the pit or tank. A reliable and appropriate connector for removably attaching pipe or conduit to the adapter portion in a heavy liquid environment includes, for example, a camlock 19.

[0014] The pump body 20 is preferably provided with one or two handles, such as handles 32 connected to the pump lid 12. Such handles 32 allow the pit pump to be easily grasped and carried. Such handles can also be useful for fishing the pit pump out of a mud pit with a pole and hook.

[0015] The bearing block assembly 7 operatively connects the hydraulic drive motor 3 to the impeller 18 of the pump 28, whereby the submersible hydraulic drive motor 3 is connected to but spaced apart from the pump 28. According to the presently-most preferred embodiment of the invention, the bearing block assembly 7 is at least about 6 inches long, which helps provide an adequate length of isolation between the pump and the hydraulic drive motor.

[0016] According to the presently most-preferred embodiment, the bearing block assembly 7 includes a bearing housing 7 a and a drive shaft 7 b operatively positioned for rotational movement within the bearing housing 7 a, whereby rotational movement can be transferred from the hydraulic drive motor 3 to the impeller 18 of the pump 28. The drive shaft 7 b is operatively mounted for rotational movement on bearings (not shown) in the bearing housing 7 a. The drive shaft 7 b is adapted to be operatively connected at one end thereof to the rotational output of the hydraulic drive motor 3, and adapted to be operatively connected at the other end thereof to the impeller 18.

[0017] The bearing block assembly 7 and the hydraulic drive motor 3 are removably secured together using, for example, a plurality of ½″×¾″ UNC bolts 1 with ½″ SAE washers 2. Depending on the relative sizes of the parts involved, adapters, such as splined adapter 4, splined spacer 5, and spacer plate 6, can be appropriately used for operatively adapting the rotational output of the hydraulic drive motor 3 and the upper end of the drive shaft 7 b of the bearing block assembly 7.

[0018] The bearing block assembly 7 and the lid 12 of the pump body 20 are removably secured together using, for example, a plurality of ½″×¾″ UNC bolts 13 with ½″ SAE washers 14. According to the presently most-preferred embodiment of the invention, a silicone sealant 33 is used to help seal the connection between the bearing block assembly 7 and the lid 12 of the pump body 20.

[0019] The lower end of the drive shaft 7 b of the bearing block assembly 7 is adapted to connect to and drive the impeller 18. According to the presently-most preferred embodiment, a ¼″×2″ square key 17 is positioned between the lower end of the drive shaft 7 b and the impeller 18, which causes the impeller 18 to rotate with the drive shaft 7 b of the bearing block assembly 7. The impeller 18 is retained on the lower end of the drive shaft 7 b using, for example, a UNC crown nut 21 and a cotter pin 22. Depending on the relative sizes of the parts involved, an adapter or spacer, such as 1″ SAE washer 16, can be appropriately used for operatively adapting the lower end of the drive shaft 7 b and the impeller 18.

[0020] Of major importance is that the rotational movement of the drive shaft 7 b within the bearing block assembly 7 be well lubricated. According to the presently most-preferred embodiment of the invention, a grease nipple 9 and a bleeder nipple 8 are provided in the bearing housing 7 a for maintaining adequate grease lubrication within the bearing block assembly 7.

[0021] The bearing block assembly 7 is most-preferably lubricated with a multi-purpose, extreme-pressure (“E.P.”), water-resistant, and high-temperature grease. Such a grease is suitable for wet and hot applications, preferably specified up to +300° F.

[0022] At the high local temperatures associated with metal-to-metal contact, an E.P. additive combines chemically with the metal to form a surface film that prevents the welding of opposing asperities, and the consequent scoring that is destructive to sliding surfaces under high loads. Reactive compounds of sulfur, chlorine, or phosphorus are used to form these inorganic films. A suitable grease includes a “moly” grease. Moly is short for molybdenum disulfide, a solid lubricant and friction reducer, colloidally dispersed in some oils and greases. The micron or sub-micron size molybdenum disulfide (moly) particles tends to bond to the metal surface. This plating action is believed to improve the metal finish and develop a smoother surface, thus reducing friction. A presently most-preferred commercially-available grease is Schaeffer's Moly Pure Ultra 800 E.P., water-resistant, and high-temperature grease.

[0023] The bearing block assembly 7 separates the hydraulic drive motor 3 from the pump 28, making it difficult for water in the fluid or particles in the fluid from getting through to the hydraulic drive motor 3. Maintaining the proper grease lubrication in the bearing block assembly 7is simple, and allows the pit pump to operate reliably and with minimal down time for service or repair.

[0024] The embodiments shown and described above are only exemplary. Many details are often found in the art, therefore, such details are neither shown nor described. It is not claimed that all of the details, parts, elements, or steps described and shown were invented herein. Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in the detail, especially in matters of shape, size and arrangement of the parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms used in the attached claims.

[0025] The restrictive description and drawings of the specific examples above do not point out what an infringement of this of this patent would be, but are to provide at least one explanation of how to make and use the invention. The limits of the invention and the bounds of the patent protection are measured by and defined in the following claims. 

What is claimed is:
 1. A pit pump comprising: a submersible hydraulic drive motor; a pump further comprising a body, a fluid inlet in the body, a fluid outlet in the body, and an impeller operatively positioned in the body, whereby fluid can be pumped between the fluid inlet and the fluid outlet; and a bearing block assembly operatively connecting the hydraulic drive motor to the impeller of the pump, whereby the submersible hydraulic drive motor is spaced apart from the pump.
 2. The pit pump according to claim 1, wherein the hydraulic drive motor is further provided with quick coupler fittings for connecting hydraulic fluid lines to the hydraulic drive motor.
 3. The pit pump according to claim 1, wherein the body of the pump further comprises a lid portion, whereby the interior of the pump can be accessible for assembly and maintenance.
 4. The pit pump according to claim 1, wherein the body of the pump further comprises at least one handle for grasping or carrying the pit pump.
 5. The pit pump according to claim 1, wherein the bearing block assembly is at least about 6 inches long, which helps provide an adequate length of isolation between the pump and the hydraulic drive motor.
 6. The pit pump according to claim 1, wherein the bearing block assembly further comprises a housing and a drive shaft operatively positioned for rotational movement within the housing, whereby rotational movement can be transferred from the hydraulic drive motor to the impeller of the pump.
 7. The pit pump according to claim 1, wherein the bearing block assembly further comprises a grease nipple and bleeder nipple for maintaining grease lubrication within the bearing block assembly.
 8. The pit pump according to claim 1, wherein the bearing block assembly is lubricated with an extreme-pressure, water-resistant, and high temperature grease. 